Lake Ngaroto is a peat lake in Waipa District of New Zealand.
Located 19 km south of Hamilton and 8 km north-west of Te Awamutu, it has a surface area of , making it the largest of the Waipa peat lakes.
The New Zealand Ministry for Culture and Heritage gives a translation of "the lakes" for NgÃÂroto.
The Battle of Hingakaka was fought nearby, and the sacred carving Te Uenuku lost at this time. It was re-discovered in 1906, and now resides in the Te Awamutu Museum. In 2016 a pou, representing 7 atua, was erected near the spot where Te Uenuku is thought to have been found.
The Ngaroto Drainage Board was formed in 1898. By 1928 hundreds of acres, formerly lake-bed, had been drained.
Restoration of the lake began in 1995.
The lake is hypertrophic, leading to eutrophication. It has very high levels of nutrients, microscopic algae and suspended sediment and its water clarity is low and decreasing by around a year. A health warning was issued in 2020 for cyanobacteria. Cyanobacteria killed fish and birds in 2022. The lake is now monitored by a harmful algal bloom indicator, a buoy to measure pigment produced by the cyanobacteria and satellite imagery.